Product Description
5/8"-18 UNF Grade 5 Zinc Plated Hexagon Head Bolts With Shank
These 5/8" UNF hexagon head bolts are manufactured from high-tensile Grade 5 steel and finished with zinc plating for additional protection against corrosion. Available in lengths from 2" to 7", they feature a partially threaded construction with an unthreaded shank through part of the fastening.
The 5/8"-18 UNF thread has 18 threads per inch and is suitable for automotive, agricultural, machinery, restoration and general engineering applications requiring a fine-pitch Unified fastener. It must be paired with a matching 5/8"-18 UNF nut or internally threaded component.
- Thread size: 5/8"-18 UNF
- Threads per inch: 18 TPI
- Available lengths: 2", 2 1/4", 2 1/2", 2 3/4", 3", 3 1/2", 4", 4 1/2", 5", 6" and 7"
- Thread form: Unified National Fine
- Thread coverage: Part threaded with unthreaded shank
- Threaded length up to 6" overall: 1 1/2" nominal
- Threaded length over 6" overall: 1 3/4" nominal
- Material: High-tensile steel
- Strength grade: SAE Grade 5
- Approximate metric comparison: Property class 8.8
- Finish: Zinc plated
- Head style: Hexagon head
- Spanner or socket size: 15/16" AF
- Nominal head thickness: Approximately 25/64"
- British dimensional standard: BS 1768
- American dimensional standard: ASME B18.2.1
- Thread standard: ASME B1.1
The solid, unthreaded shank can pass through the clearance holes of assembled components. Selecting the correct bolt length can keep the threaded section away from the principal shear plane and provide improved support through the joint.
SAE Grade 5 is a recognised high-tensile imperial fastener grade and is broadly comparable in strength to metric property class 8.8. These grading systems are not identical or directly interchangeable, so the correct thread system and specified strength grade must always be used.
The zinc-plated finish provides protection for indoor and moderately exposed applications. It is not a replacement for galvanised or stainless steel in highly corrosive, marine or continuously wet environments.
Complete your fastening assembly with suitable nuts and washers. For help identifying imperial threads, please see our Thread Data Guide and Spanner Sizes Guide.
Please note: Bolt length is measured from beneath the hexagon head to the end of the bolt. Threaded and shank lengths are nominal reference dimensions and may vary within manufacturing tolerances. If any dimension, strength grade or standard compliance is critical, please contact us before ordering.
| A | B | C | D | E | F | G |
| 5/8" | 2 1/2" | 1 1/2" | 15/16" | 3/8" | 18 | 1" |
| 5/8" | 2 1/4" | 1 1/2" | 15/16" | 3/8" | 18 | 3/4" |
| 5/8" | 2 3/4" | 1 1/2" | 15/16" | 3/8" | 18 | 1 1/4" |
| 5/8" | 2" | 1 1/2" | 15/16" | 3/8" | 18 | 1/2" |
| 5/8" | 3 1/2" | 1 1/2" | 15/16" | 3/8" | 18 | 2" |
| 5/8" | 3" | 1 1/2" | 15/16" | 3/8" | 18 | 1 1/2" |
| 5/8" | 4 1/2" | 1 1/2" | 15/16" | 3/8" | 18 | 3" |
| 5/8" | 4" | 1 1/2" | 15/16" | 3/8" | 18 | 2 1/2" |
| 5/8" | 5" | 1 1/2" | 15/16" | 3/8" | 18 | 3 1/2" |
| 5/8" | 6" | 1 1/2" | 15/16" | 3/8" | 18 | 4 1/2" |
| 5/8" | 7" | 5 1/4" | 15/16" | 25/64" | 18 | 1 3/4" |
Please Note: Specifications given are intended as a guide only. If critical to your project please check with us first.
